Why do seismologists need measurements from three different locations to find the epicenter of an earthquake?
Jul 29, 2010
in
Earthquake Questions
Does anyone know? Please don’t answer ‘idk’ or something like that.
Thanks
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2 comments
Wounded Duck on July 29, 2010 at 10:48 pm
Triangulation
A.Ganapathy India on July 29, 2010 at 10:48 pm
The seismograph will record the followings.
1. Arrival time of P ,S,L & R waves,
2.The amplitude of the waves,
3. The frequency of the waves.
The arrival time of S wave minus P wave multiplied by speed difference gives you the distance of epicenter ( Focus point ).You can tell only the distance of epicenter from the seismographic station.Therefore you can only draw a circle of that distance as radius. The epicenter may be any where on the circumference on the circle. There fore we plot the circle from three stations from three direction.The three circles will meet at a single point.That point is the epicenter. But I have designed one instrument called direction finder nothing but the concept of ancient direction finder which was in use in China for many years. With this direction finder to gether with single seismograph picture you can find out approximate epicenter that will help to suspect Tsunami.I am the one issued the warning 2 hours before Tsunami struck our coast.